Door operator



Oct. 14, 1969 M, K. RICHMOND 3,471,971

DOOR OPERATOR Filed sept.y 28. 19e? E) n hmmag United States Patent O 3,471,971 DOOR OPERATOR Moscow K. Richmond, 2819 Butler Ave., Los Angeles, Calif. 90064 Continuation-impart of application Ser. No. 374,768, June 12, 1964. This application Sept. 28, 1967, Ser. No. 671,466

Int. Cl. E052? 11/00, 15/00 U.S. Cl. 49--199 6 Claims ABSTRACT OF THE DISCLOSURE A guide track having a longitudinal slot at the bottom, encloses, supports, and guides a traveling carriage moving over a linear path to open and close a door, especially an overhead type door, which is connected to the carriage. The carriage is pulled back and forth within the track by a flexible tension member which is likewise closed within the track. The track is preferably hinged in order to fold and shorten it during shipping. Means are provided on the carriage to adjust the tension and the length of the tension member.

CROSS REFERENCE TO RELATED APPLICATIONS The present application is a continuation-in-part of my copending application Ser. No. 374,768 led June 12, 1964 for Door Operator 4with Speed-Change Sensing Mechanism.

BACKGROUND OF THE INVENTION The general field of the present invention is door operators which are designed to open and close doors, particularly those traveling vertically as is the case With overhead type doors.

However, the present invention is related more particularly to improvements in the track for supporting and guiding the carriage to which doors connected by a rigid link whereby movement of the carriage transmits the desired motion to the door.

While door operators of this type may be employed in any location, they have recently become much more commonly installed in residential garages and the like where factors of appearance, freedom from maintenance, reliable operation, and the like are relatively of greater importance than is the case with industrial or commercial installations.

If the mutually engaging surfaces of the track and carriage are exposed, they gather dust. These surfaces are preferably lubricated and so all the dust falling upon them adheres, even though the lubricant is relatively thin and dry. After a while the mixture of lubricant and dust tends to become gurnmy and to impede, rather than to help the travel of the carriage along the track.

These exposed surfaces are unsightly and objectionable to the average home owner. In addition, they provide some element of hazard since objects contacting them may become caught between the relatively moving surfaces. Elimination of these problems may provide the basis for a strong appeal to a buyer of one type of door operator over another so that improvement in these respects can provide a signicant commercial advantage.

Accordingly, it is a general object of the present invention to provide an improved design of a track and carriage which is supported and guided thereby, as a part of a door operator of the character described.

More particularly, it is an object of the present invention to provide a track design Iwhich encloses as fully as possible the traveling carriage and all of the surfaces ICC on the carriage and track which are in sliding contact with each other, as well as to enclose the tension member -which moves the carriage along the track.

A further object is to provide a track design that, when the track is connected to the power unit enables the operator as a whole to be shortened to reduce maximum length during handling, storing and shipping.

SUMMARY OF THE INVENTION The present invention is embodied in a door operator comprising a tubular track having an extending slot at one side of the track, a carriage movable longitudinally of the track While being entirely supported and guided by interior surfaces of the track, a portion of the carriage extending out through the longintiudal slot to permit connection to a door, and means for moving the carriage back and forth along the track, such means including a chain or the like enclosed in the tubular track.

The track is hinged to permit folding and is provided with a bracket to hold the hinged sections aligned when the track is extended, said bracket contacting only exterior surfaces of the track so that the carriage, which is guided only by the interior surfaces of the track, moves past the joint and the bracket freely. The carriage construction includes a novel means for adjusting the length and tension of the chain or other power transmitting means moving the carriage.

BRIEF DESCRIPTION OF THE DRAWINGS How the above objects and advantages of the present invention, as well as others not specifically referred to herein, are attained will be more readily understood by reference to the following description and to the annexed drawings, in which:

FIG. 1 is a side elevation of a complete door operator with guide track and traveling carriage constructed according to the present invention, with the traveling Carriage connected to an overhead type door.

FIG. 2 is a side elevation of the track in folded position, portions of the track and operator being broken away.

FIG. 3 is a fragmentary vertical section on line 3 3 of FIG. 1.

FIG. 4 is a transverse cross-section on line 4-4 of FIG. 3.

FIG. 5 is a fragmentary side elevation of the track and carriage traveling thereon.

FIG. 6 is an enlarged vertical median section through a portion of the track and the carriage traveling thereon.

FIG. 7 is a vertical transverse section through the track and carriage on line 7-7 of FIG. 6.

FIG. 8 is a cross-section on line 8 8 of FIG. 1 of the drive sprocket and its drive shaft only.

Referring now to the drawings, and particularly to FIG. 1, it will be seen that the door operator comprises a prime mover, preferably electric motor 10, mounted on a skeleton frame 11, a power transmission system indicated generally at 12 and connected to the output shaft of motor 10, and a track 14 along which travels carriage 1S. Frame 11 is rigidly connected to one end of track 14 to be supported thereby. The operator may be mounted in any suitable manner, as by attaching hanger 16 near one end of the track and to a structural member of the building as at 17, while the other end of the track is attached by bracket 18 to the wall or lintel 19 over the doorway. Traveling carriage 15 is connected by rigid link 20 to door 21 which is to be raised `and lowered by movement of the carriage, door 21 being here shown as of the overhead type although it will be realized that the construction of the door and the path through which it moves to open and close are not limitative upon the present invention.

The power transmission system may be of a suitable type which transmits power from prime motor to carriage 15. The system herein illustrated is described in greater detail in my co-pending application referred to above and which may be referred to for additional details of construction. Generally, the output shaft 24 of motor 10 has mounted on it a drive pulley from which power is transmitted through an arrangement of belts, pulleys, chains, and/or sprockets to shaft 25 on which is mounted drive sprocket 26. The diameters of the several pulleys and sprockets are so chosen as to effect a desirable speed reduction between the output shaft of motor 10 and the final drive, in this case sprocket 26; but it will be realized that in the broader aspects of the present invention these details of the power train are not limitative upon the present invention.

Sprockets 26 on shaft 25 is the output member of the power train so far described. Sprocket 26 has trained over it roller chain 32 which is part of a flexible power transmitting member connected to carriage to move the carriage along track 14. A chain and sprocket arrangement are preferred for the driven portion of this member because of the positive drive characteristics provided thereby. While the entire power transmitting element may be a roller chain, it is preferred to have only that portion of the element which necessarily passes over the drive sprocket a chain, the remainder of the flexible member being a steel cable 33 or the like attached at one end to chain 32. This cable portion passes over idler pulley 34 (FIG. l), the free end of cable 33 being anchored to the forward end of carriage 15, as shown at 33a in FIG. 6. One end of chain 32 is also attached to carriage 15, as shown in FIGS. 5 and 6. With both ends of the exible member attached to the carriage, the power transmitting member 32-33 becomes in effect an endless member and the carriage can be pulled by it in either direction along the track 14.

Track 14 is a tubular member with a longitudinally extending slot along one side. This slot, indicated at 35 in FIG. 4, is located at the underside of the track and extends for substantially the full length of it. Track 14 is a. common type of channel member with inwardly turned anges 37 along the two sides of slot 35 and is normally rectangular in cross-section. However, tubular members of other shapes may be employed if desired; but the rectangular shape is preferred since it gives the greatest stability to movement of the carriage.

Track 14 is normally several feet long, typically about 12 feet. In order to facilitate shipment of this long member, it is preferably divided into two more or less equal sections which are hinged together by an externally located hinge, as at 36 in FIGS. 2 and 4. Hinge 36 permits the sections to be folded over against one another into side-by-side or face-to-face relation as shown in FIG. 2 for shipping, and t0 be extended into prolongation of each other to form a single continuous track as shown in FIG. 1. To hold these two track sections in mutual orientation in the extended position, clamp 38 is provided. Clamp 38 consists of two sections conforming in size and shape to the exterior surface of the tubular track and which have opposed mating flanges 38a through which pass bolts 39 to fasten together the two halves of the clamp. Clamp 38 engages the abutting ends of the two track sections to hold them rigidly in position to provide, in effect, a single continuous track. Hinge 36 holds the track sections against endwise separation. It will be noted that the clamp engages only outer surfaces of the tubular track and does not cross slot 35. Thus the clamp does not come into contact with carriage 15 which, as will be explained, engages the internal surfaces of the track.

Carriage 15 which travels along track 14 is shown in detail in FIGS. 5, 6 and 7. Generally speaking, it comprises two sections, a guiding and supporting section that is contained inside the channel forming track 14 and an outside section to which chain 32 and operating link 20 are connected. In the preferred embodiment illustrated in the drawings, these two sections 40 and 41, respectively, are shown as being channel-shaped in crosssection and both alike. However, this is for economy and convenience only and it is not necessary that the two sections be similar.

Section 40 which rides inside track 14 has an exterior surface which conforms in size and shape to the interior surface of track 14 in order that the track is most sufciently supported and guided as the carriage slides along the interior of the track. The same general configuration from the outside section 41 is convenient as it provides a suitable means for receiving bolt 43 by which connecting link 20 is pivotally connected to the carriage. The two depending legs of channel section 41 also provide a convenient arrangement `for receiving a transversely extending trunnion 44 through which passes adjusting screw 45. Screw 45 is threaded into the trunnion and has the forward end 45a reduced in diameter to be inserted between the side plates of the roller chain, as shown in FIG. 6. This forward tip 45a of reduced diameter provides a shoulder on the screw which engages the chain links to provide a thrust on the chain as the adjusting screw is tightened. Chain 32 passes through openings 40a and 41a in the two track sections, respectively, to engage adjusting screw 45. The angularity of the path followed by the chain brings the chain into firm contact with one edge of opening 41a and thus ensures not only that the chain is held tight by adjusting screw 45 but that the chain is locked on the forward end of the adjusting screw and cannot jump off. The length of the threaded portion of screw 45 is preferably equal to two or three links of the chain so that adequate range of movement is provided on the adjusting screw to engage any selected one of several chain links and to provide the proper tension in the endless member 32-33.

The two sections 40 and 41 of the carriage are held spaced apart by tubular spacers 46 through which pass bolts 47 to fasten the two carriage sections together. Spacers 46 pass through the longitudinal slot in the bottom of the track and hold the exterior portion of the carriage below and clear of the exterior surface of the track, thus allowing the carriage to move back and forth along the track while clearing clamp 38 at the joint in the track. From this arrangement, it will be seen that the carriage is supported and guided solely by interior surfaces of the track while spacers 46 merely provide posts connecting the exterior portion of the carriage to the interior guiding portion.

Long unsupported runs of chain have a tendency to vibrate, especially when driven by a sprocket of relatively small diameter as is the case with sprocket 26. This vibration can be substantially eliminated by a vibration damping means in the form of a narrow metal shoe 48 on plate 49. The shoe is stationary and bears lightly against the moving rollers of the upper run of chain 33, as shown in FIG. 3. The shoe is preferably spaced from sprocket 26 `by a short distance. A similar stationary shoe (not shown) is located near idler sprocket 34. Plate 49 is bolted to track 14 and may be adjusted in position. The upper run of the chain also preferably carries a rubber grommet (not shown) which engages and slides over the inside surface of track 14 to dampen the vibration of intermediate section of the upper run when long enough to require damping.

A typical electrical circuit for the door operator is shown in detail in my co-pending application Ser. No. 374,768 and will not be repeated here.

The track described is enclosed as far as possible to exclude dust and dirt from the surfaces in sliding contact. The carriage is guided by internal surfaces that can be lubricated and kept clean with minimum maintenance. Also the exible tension driving member is enclosed where it is shielded to exclude foreign objects that might become entangled in it. The track is preferably in two sections hinged together, permitting the overall length of the operator to be greatly reduced for shipment or convenience in handling and transportation even when uncrated.

FIG. 8 shows in section a preferred mounting for drive sprocket 26 on shaft 25 which drives the sprocket. Shaft 25 is rotatably mounted in bearings, not shown. In between shaft 25 and the hub of sprocket 26 is sleeve 52 of neoprene or other elastomeric material which can be bonded to both the metal hub and shaft. By bonding the sleeve to the drive shaft or other metal core and to the sprocket, torque can be transmitted through the sleeve from one member to the other in sutiicient magnitude to drive member 32-33.

This construction offers several advantages. One of the main advantages is that it acts to deaden the sound and vibration created by the chain traveling over the sprocket. If there were a metal-to-metal contact between the sprocket and the shaft 25, the tendency is for sound to travel into the other parts of the operator and to be magnied by diaphragm action. However, the sound energy is diminished as it passes through the layer of neoprene or similar material and the result is to make the device run much more quietly.

Also, the neoprene is compressible and consequently it can permit minor changes in the position and alignment of sprocket 26 caused by tension in the drive chain with resultant greater tolerances in the manufacture of the device.

Of course, shaft 25 may be mounted in any kind of bearings, not shown in the drawings, either journal or ball bearings. Likewise, shaft 25 can -be replaced by a metal sleeve or other core which in turn is mounted upon a stationary shaft thus providing a journal bearing for sprocket 26. It will be evident without further illustration that sprocket 26 may instead of being a drive member may be an idler over which the chain is trained. In this latter case, it is not necessary that the sprocket have teeth to engage the chain links but a ridge around the hub may be adequate for these purposes.

It will be apparent from the foregoing description that various changes in the specific details and construction of the various elements constituting the present invention may be made without departing from the spirit and scope of the present invention. Accordingly, it is to be understood that the foregoing description is considered as being illustrative of, rather than limitative upon, the invention disclosed herein.

I claim:

1. In a door operator, the combination comprising:

a tubular track having a longitudinally extending slot in one side, said track having two opposing, spaced sidewalls substantially parallel to the slot and and to each other and disposed respectively at opposite sides of the slot;

a carriage movable longitudinally of the track, said carriage comprising a supporting and guiding section, said section being of channel shape and slidably engaging the track only on interior surfaces of the track, a second section outside the track, and means movable within the slot connecting together the two carriage sections but holding the second section spaced from exterior surfaces of the track;

means disposed substantially inside the track for moving the carriage back and forth along the track, said means comprising a length of roller chain passing through the channel-shaped section and the slot in the track to the second carriage section;

manually adjustable tensioning and connecting means for connecting the roller chain to the carriage in a substantially non-yielding but spatially adjustable manner;

and a link pivotally connecting the carriage to a door to be moved.

2. In a door operator as claimed in claim 1, the combination in which the track is in two sections hinged together;

and which also includes external clamp means engaging three sides of the track at the abutting ends of the two track sections to hold the sections rigidly in prolongation of each other.

3. A door operator comprising:

a tubular track having at two sides opposed, spaced, substantially parallel side walls and at a third side a longitudinally extending slot of lesser Width than the spacing between the side walls and located substantially midway between said side walls;

a carriage having a channel-shaped section inside the tubular track with substantially parallel side walls engaging said track side walls to guide the carriage as it moves longitudinally of the track;

said carriage also having a second channel-shaped section with spaced side walls located outside the track;

said carriage also having post means of lesser width than the slot section projecting outwardly through said slot for connecting together the two carriage sections;

means pivotally connected between the walls of the second carriage section for connecting the carriage to a door to be moved;

and means including a flexible tension member substantially inside the track and connection at both ends to the carriage for moving the carriage back and forth along the track.

4. In a door operator as claimed in claim 3, the combination that also includes a shoe slidably engaging the tension member between supports therefor to dampen vibration in the tension member.

5. In a door operator as claimed in claim 3, the combination in which the flexible tension member includes at one end a length of chain;

and which also comprises adjustable tensioning means including a screw threaded member pivotally mounted to swing about a transverse axis and having a shouldered forward portion engaged by the chain.

6. In a door operator as claimed in claim 3, the combination in which the exible tension member includes a length of chain;

and which also comprises a metal driving sprocket engaging the chain, a metal core rotatably mounted, and a sleeve of elastomeric material interposed between the metal core and the metal sprocket and bonded to both the core and the sprocket whereby torque can be transmitted between the core and the sprocket.

References Cited UNITED STATES PATENTS 1,962,475 6/ 1934 Blodgett 160-188 X 2,713,970 7/1955 Kueser l64-11 X 2,736,553 2/1956 Brown 49-199 X 2,747,864 5/1956 Miller 160--188 X 2,753,179 7/1956 Hahn 49-199 X 2,848,884 8/1958 Maude 64-11 X 3,314,469 4/ 1967 Kaufman et al. 160-159 DENNIS L. TAYLOR, Primary Examiner U.S. Cl. X.R. -188 

